Non-controlling Interest - Ownership of common units in RMCO (Details) - RMCO, LLC - shares	Dec. 31, 2019	Dec. 31, 2018
Shares
Non-controlling interest ownership of common units in RMCO	12,559,600	12,559,600
Holdings outstanding Class A common stock (equal to Holdings common units in RMCO)	17,838,233	17,754,416
Total number of common stock units in RMCO	30,397,833	30,314,016
Ownership Percentage
Non-controlling interest ownership of common units in RMCO as a percentage	41.30%	41.40%
Holdings outstanding Class A common stock (equal to Holdings common units in RMCO)	58.70%	58.60%
Total percentage of common stock units	100.00%	100.00%
RIHI
Ownership Percentage
Non-controlling interest ownership of common units in RMCO as a percentage	41.30%

The noncontrolling interest in net assets of the subsidiary, in number of common stock units owned.

No definition available.

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The parent entity's interest in net assets of the subsidiary, in number of common stock units owned.

No definition available.

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No definition available.

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Aggregate percentage of subsidiary's common units outstanding.

No definition available.

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No definition available.

Number of common units of ownership outstanding of a limited liability company (LLC).

No definition available.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

No definition available.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

No definition available.

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